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Background: Conformal Radiotherapy techniques adapting to the ballistics of delineated volumes allowed significant reduction in excess radiation induced mortality however the increasing number of long-term survivors and expanding use of cardiotoxic drug highlight the persistent need for maximal cardiac possible sparing. The low dose volume of left ventricle are better predictor of acute coronary events than mean heart dose. Materials and Methods: 38 post-MRM patients were randomized to treatment by 3Dimensional Conformal Radiotherapy (3D CRT) and Intensity Modulated Radiotherapy (IMRT) technique. Two tangential beams were used in 3D CRT technique while five to seven (mostly tangential beams) were used in inversely planned IMRT technique. The dose volume parameters of planning target volume, heart and left ventricle were compared. Results: The dosimetry of Planning target volume showed significantly better coverage in IMRT technique (D90, D95) however the D50 was comparable in both the techniques. In dosimetry of heart, the high dose volumes (V30, V40) were nearly comparable in both the techniques. The other dose volume parameters (V5, V10, V20, V25, D33, D67, D100) and the mean dose were significantly lesser in 3D CRT technique along with significantly better sparing of left ventricle (Dmean and V5). Conclusion: The dosimetry of target volume was better with IMRT technique, but this was accompanied by a huge increase in dose to whole heart and specifically the left ventricle which has strong potential to translate into an increased cardiotoxicity. A better distribution of the target region may be obtained by multiple segmentation of the two tangential fields in 3D CRT plans with further reduction in dose to heart and left ventricle.
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Objective To compare the efficacy and toxicities between preoperative concomitant boost intensity-modulated radiotherapy (IMRT) and 3-dimensional conformal RT (3-DCRT) for locally advanced rectal cancer.Methods A prospective study from May 2010 to May 2015.A total of 130 patients with histologically confirmed,newly diagnosed,locally advanced rectal adenocarcinoma (cT3-T4 and/or cN +) located within 10 cm from the anal verge were included in this study.The patients were divided into IMRT and 3D-CRT groups by random number table method.Sixty-six patients were treated with IMRT,and the other sixty-four patients were treated with 3-DCRT.In the IMRT group,the prescription dose was 1.8 Gy/fraction to 45 Gy to the pelvis and 2.2 Gy/fraction to 55 Gy to the gross tumor volume simultaneously.The 3D-CRT prescription was 45 Gy in 25 fractions to the pelvis.Capecitabine (1 650 mg· m 2 · d-1) was given twice daily from days 1 to 14 and days 22 to 35 during RT in both arms.Total mesorectal excision (TME) was scheduled 6-8 weeks after the completion of chemoradiation.Results There were no significant differences in age,gender,tumor location,pathological differentiation degree and clinical stage between the two groups.Two patients withdrew from the study:one for grade 3 radiation dermatitis in IMRT group and the other for grade 3 fatigue in 3D-CRT.There was no significant difference in hematologic or nonhematologic toxicities between the two groups.No grade 4 or 5 toxicity was observed in either group.Compared with conformal radiotherapy,IMRT did not increase the difficulty of surgery.No significant difference was found in type of surgery or postoperative complications between the two groups.The rate of tumor regression grade (TRG) 4 (pathologic complete response,pCR) was 22.7％ for IMRT and 15.6％ for 3D-CRT,respectively(P ＞ 0.05).The rate of both TRG4 and 3 was 42.4％ for IMRT and 25.0％ for 3D-CRT,respectively (x2 =4.406,P=0.036).Conclusions Neoadjuvant concomitant boost IMRT is feasible and has a higher histopathological regression for patients with locally advanced rectal cancer.Trial registration Chinese clinical trial registry,ChiCTR-IN R-16008004.
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Objective To compare the dosimetric parameters of volumetric modulated arc therapy(VMAT),fixed field intensity modulated radiation therapy(IMRT)and three-dimensional conformal radiotherapy(3D-CRT)in the radiotherapy for the patients with locally recurrent nasopharyngeal carcinoma, and to analyze their characteristics. Methods Twelve patients with locally recurrent nasopharyngeal carcinoma were treated with VMAT, IMRT and 3D-CRT plan designed by Pinnacle 9.2 and Preciseplan 2.03 treatment planning system.The dosimetric parameters of targeted volumes and organs at risk were compared between three groups. Results The conformation indexes (CI)of VMAT and IMRT plans were similar,and they were both better than 3D-CRT plan,the difference was significant(P0.05).The monitor units(MU)and beam time in 3D-CRT group were better than those in other two groups,and VMRT group was better than IMRT group,the statistical differences were observed between three groups (P0.05).The doses of the spinal cord,optic nerve,optic chiasm and temporal lobe of brain in VMAT and IMRT groups were better than those in 3D-CRT group,there were statistical differences between them(P0.05).Conclusion There are differences of the targeted dose distribution between the three kinds of radiation technology, while VMAT and IMRT plans can cover the targeted areas and reduce the received doses of organs at risk.The CI,MU and beam time of VMAT plan are better than those of IMRT plan. 3D-CRT plan only has advantage in the MU and beam time.
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Objective To analyze the therapeutic effect of three-dimensional conformal involvedfield radiotherapy (3D-CRT)combined with chemotherapy on limited disease stage small cell lung cancer (LD-SCLC).Methods The clinical data of 85 patients of LD-SCLC treated with 3D-CRT at the dose of 2 Gy/fraction,5 fractions per week for 5 - 7 weeks,with the median dose of 50 Gy ( 46 - 66 Gy),combined with 4 -8 cycles chemotherapy,64 males and 21 females,aged 29 -76,were collected and analyzed.Results The complete remission rate,partial remission rate,stability rate,and total effective rate were 36.5％,52.9％,10.6％,and 89.4％,respectively.The median survival time was 18 months,with the 1-,2-,and 3-year overall survival rates of 65.9％,33.8％,and 15.9％,respectively.The local recurrence rate,distant metastasis rate,and local recurrence + distant metastasis rate were 15.2％ (9/85),49.2％ (29/85),and 35.6％ (21/85),respectively.Body weight,response to therapy,cycles for chemotherapy,and concurrent chemo-radiotherapy were all independent prognostic factors for LD-SCLC.Cox muhivariable regression was used to analyze the prognostic factors.Conclusions Involved-field radiotherapy is effective for LD-SCLC.Distance metastasis is the main cause of treatment failure.
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ObjectiveTo evaluate the instant response and side effects of hypofractionated high-dose 3-dimensional conformal radiotherapy (3-DCRT) for esophageal carcinoma treatment.MethodsSixty-nine patients with esophageal carcinoma were treated by 3-DCRT and 91 patients with routine radiotherapy.The prescribed dose was from 3000 to 4500 cGy in 3-DCRT group, with fractionated dose 300 cGy, one dose a day and five doses a week.The reference dose curve was the 90％ of the isodose curve.For the routine radiotherapy group,the prescribed dose was from 4000 to 6600 cGy,fractionated by 180 ～200 cGy a time,once a day and 5 times a week.Results At the end of the radiotherapy, 3-DCRT produced CR 42.0％ (29/69) , PR 49.3％ (34/69) and instant response rate 91.3％, while routine radiotherapy produced CR 35.2％ (32/91), PR 59.3％ (54/91) and instant response rate 94.5％, respectively.The difference was not significant between the two groups(P ＞ 0.05) .The survival rates one year after the treatment were 82.6.0％ (57/69)and 84.6％ (77/91) ,respectively.The acute radiation esophagitis rate was 66.7％ (46/69) in 3-DCRT group and was 64.8％ (59/91) in routine radiotherapy grouprespectively.ConclusionHypofractionated high-dose 3-DCRT is feasible for treatment of esophageal carcinoma.
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Background and purpose: Cerebral gliomas is one of the common brain tumors, and has a poor prognosis. Therefore, multidisciplinary treatment strategy has been much investigated recently. This study investigated the efficacy of 3 dimensional conformal radiotherapy (3D-CRT) concurrent with Temozolomide chemotherapy in the treatment of postoperative cerebral gliomas. Methods: Sixty-two patients with cerebral glioma who had residual tumor surgery after surgery were randomized into 3D-CRT group (radiotherapy group, n=31) and 3D-CRT concurrent chemotherapy group (chemoradiotherapy group, n=31) prospectively. All patients received a dose of 50-60Gy/25-30F/5-6 weeks by 6MV-X ray, 1fx/day, 5 times a week. Chemotherapy regimen was Temozolomide: 75 mg/(m~2·d),concomitantly with radiotherapy,followed by 150-200mg/(m~2·d)for 5 days,28 days per cycle for total 3-6 cycles. Results: The total response rate was 35.3% (11/31) in the radiotherapy group, and 61.3% (19/31) in the chemoradiotherapy group. The difference was significant (P=0.042). But no significant difference was observed in terms of survival in the two groups (P=0.263). Stratified analysis showed that patients with grade Ⅲ gliomas in chemoradiotherapy group had better prognosis than those in the radiotherapy group (P=0.043). Conclusion. 3D-CRT concurrent with chemotherapy can improve the survival of pathological grade Ⅲ gliomas.
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PURPOSE: In radiotherapy for cervix cancer, both 3-dimensioal radiotherapy (3D-CRT) and intensity-modulated radiation therapy (IMRT) could reduce the dose to the small bowel (SB), while the small bowel displacement system (SBDS) could reduce the SB volume in the pelvic cavity. To evaluate the effect of the SBDS on the dose to the SB in 3D-CRT and IMRT plans, 3D-CRT and IMRT plans, with or without SBDS, were compared. MATERIALS AND MEHTODS: Ten consecutive uterine cervix cancer patients, receiving curative radiotherapy, were accrued. Ten pairs of computerized tomography (CT) scans were obtained in the prone position, with or without SBDS, which consisted of a Styrofoam compression device and an individualized custom-made abdominal immobilization device. Both 3D-CRT, using the 4-field box technique, and IMRT plans, with 7 portals of 15 MV X-ray, were generated for each CT image, and prescribed 50 Gy (25 fractions) to the isocenter. For the SB, the volume change due to the SBDS and the DVHs of the four different plans were analyzed using paired t-tests. RESULTS: The SBDS significantly reduced the mean SB volume from 522 to 262 cm3 (49.8% reduction). The SB volumes that received a dose of 10~50 Gy were significantly reduced in 3D-CRT (65~80% reduction) and IMRT plans (54~67% reduction) using the SBDS. When the SB volumes that received 20~50 Gy were compared between the 3D-CRT and IMRT plans, those of the IMRT without the SBDS were significantly less, by 6~7%, than those for the 3D-CRT without the SBDS, but the volume difference was less than 1% when using the SBDS. CONCLUSION: The SBDS reduced the radiation dose to the SB in both the 3D-CRT and IMRT plans, so could reduce the radiation injury of the SB.
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Female , Humans , Cervix Uteri , Immobilization , Prone Position , Radiation Injuries , Radiotherapy , Uterine Cervical NeoplasmsABSTRACT
0.05).The effective rate of group A was 52.38%(22/42),and group B was 32.35%(11/34).There was significant differences between the 2 groups(P
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PURPOSE: Three dimensional conformal radiotherapy planning is being used widely for the treatment of patients with brain tumor. However, it takes much time to develop an optimal treatment plan, therefore, it is difficult to apply this technique to all patients. To increase the efficiency of this technique, we need to develop standard radiotherapy plans for each site of the brain. Therefore we developed several 3 dimensional conformal radiotherapy plans (3D plans) for tumors at each site of brain, compared them with each other, and with 2 dimensional radiotherapy plans. Finally model plans for each site of the brain were decided. MATERIALS AND METHODS: Imaginary tumors, with sizes commonly observed in the clinic, were designed for each site of the brain and drawn on CT images. The planning target volumes (PTVs) were as follows; temporal tumor-5.7x8.2x7.6 cm, suprasellar tumor-3x4x4.1 cm, thalamic tumor-3.1x5.9x3.7 cm, frontoparietal tumor-5.5x7x5.5 cm, and occipitoparietal tumor-5x5.5x5 cm. Plans using parallel opposed 2 portals and/or 3 portals including fronto-vertex and 2 lateral fields were developed manually as the conventional 2D plans, and 3D noncoplanar conformal plans were developed using beam's eye view and the automatic block drawing tool. Total tumor dose was 54 Gy for a suprasellar tumor, 59.4 Gy and 72 Gy for the other tumors. All dose plans (including 2D plans) were calculated using 3D plan software. Developed plans were compared with each other using dose-volume histograms (DVH), normal tissue complication probabilities (NTCP) and variable dose statistic values (minimum, maximum and mean dose, D5, V83, V85 and V95). Finally a best radiotherapy plan for each site of brain was selected. RESULTS: 1) Temporal tumor; NTCPs and DVHs of the normal tissue of all 3D plans were superior to 2D plans and this trend was more definite when total dose was escalated to 72 Gy (NTCPs of normal brain 2D plans : 27%, 8% 3D plans : 1%, 1%). Various dose statistic values did not show any consistent trend. A 3D plan using 3 noncoplanar portals was selected as a model radiotherapy plan. 2) Suprasellar tumor; NTCPs of all 3D plans and 2D plans did not show significant difference because the total dose of this tumor was only 54 Gy. DVHs of normal brain and brainstem were significantly different for different plans. D5, V85, V95 and mean values showed some consistent trend that was compatible with DVH. All 3D plans were superior to 2D plans even when 3 portals (fronto-vertex and 2 lateral fields) were used for 2D plans. A 3D plan using 7 portals was worse than plans using fewer portals. A 3D plan using 5 noncoplanar portals was selected as a model plan. 3) Thalamic tumor; NTCPs of all 3D plans were lower than the 2D plans when the total dose was elevated to 72 Gy. DVHs of normal tissues showed similar results. V83, V85, V95 showed some consistent differences between plans but not between 3D plans. 3D plans using 5 noncoplanar portals were selected as a model plan. 4) Parietal (fronto- and occipito-) tumors; all NTCPs of the normal brain in 3D plans were lower than in 2D plans. DVH also showed the same results. V83, V85, V95 showed consistent trends with NTCP and DVH. 3D plans using 5 portals for frontoparietal tumor and 6 portals for occipitoparietal tumor were selected as model plans. CONCLUSION: NTCP and DVH showed reasonable differences between plans and were thought to be useful for comparing plans. All 3D plans were superior to 2D plans. Best 3D plans were selected for tumors in each site of brain using NTCP, DVH and finally by the planner's decision.
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Humans , Brain Neoplasms , Brain Stem , Brain , Rabeprazole , Radiotherapy , Radiotherapy, ConformalABSTRACT
Elective neck irradiation is usually used as the modality of choice for the treatment of phase N 0 head and neck cancers. The increasing use of 3 dimensional conformal treatment planning has created an urgent need for new guidelines for the classification and delineation of the neck node areas. Surgical literature has provided us with valuable information in this field. The development of imaging technology has also offered us more detailed information. Several surgical and imaging methods have been proposed in this article, with the hope to give reference to most radiation oncologists. [
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Objective To evaluate the value of 3-dimensional conformal radiotherapy combined with Hydroxycamptothecin(HCPT) in the treatment of local advanced non-small cell lung cancer.Methods A total of 95 cases were enrolled and randomly assigned to treatment group and control group.The treatment group was treated with 3-dimensional conformal radiotherapy(3DCRT) combined with HCPT.The control group was treated with 3DCRT only.Results Response rate(CR+PR) is respectively 73.4 % and 62 %.The response rate of treatment group is higher than that of control group(P
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OBJECTIVE:To observe the short-term curative effects of 3-dimensional conformal radiotherapy(3DCRT) combined with taxotere on locally advanced non-small cell lung cancer.METHODS:83 patients Ⅲ a or Ⅲ b with locally advanced non-small cell lung cancer were divided randomly into the treatment and control group.The treatment group were treated with 3DCRT in combination with taxotere,while the control group were treated with single 3DCRT.RESULTS:The effective rates in the treatment and control group were 88.37% and 62.50%(P